Embodiments of the present invention relate to fuse patterns and a method of manufacturing the same. With the recent rapid spread of information media, such as computers, semiconductor devices are making rapid progress. In terms of its function, the semiconductor device is required to be operated at high speed and also to have a high storage capacity. Accordingly, the semiconductor device is developing toward the improvement of the degree of integration, reliability, a response speed, is etc.
The semiconductor device is formed by a fabrication (FAB) process of forming cells, each having an integrated circuit, by repeatedly forming circuit patterns on a substrate chiefly made of silicon and an assembly process of packaging the substrate in which the cells are formed by the cell. An electrical die sorting (EDS) process of testing electrical characteristics of the cells formed on the substrate is performed between the fabrication process and the assembly process.
The test process is performed in order to determine whether the cells formed on the substrate have an electrically good or fail state. Efforts and costs necessary for the assembly process can be reduced by removing a cell having a fail state through the test process before the assembly process is performed. Furthermore, a cell having a fail state is previously detected and may be recycled through a repair process.
The repair process is described in more detail below.
In order to improve the yield of semiconductor devices, redundant cells for replacing fail elements or fail circuits when the devices are designed are added if a fail is detected in a process of manufacturing the semiconductor devices. Fuses, together with the redundant cells, are designed in order to couple the redundant cells to the integrated circuits.
The repair process is performed to recycle cells, determined to be failed by the test process, by coupling the fail cells and the redundant cells embedded in chips using the fuses. In the repair process, formation about the locations of cells to be repaired is generated by cutting only specific fuses.
A known method of repairing a semiconductor device is described in short below.
First, after an interlayer insulating layer having a flat surface is deposited on the fuse region of a semiconductor substrate, a plurality of fuse patterns is formed on the interlayer insulating layer. An insulating layer is deposited on the result of the semiconductor substrate so that the fuse patterns are covered. Repair trenches where the insulating layer of a specific thickness remain on a reserved blowing region (i.e., the fuse patterns) are formed by etching the insulating layer in a specific thickness.
Next, known test and repair processes, including a fuse blowing process of cutting a specific fuse by radiating a laser to the fuse region of the semiconductor substrate, are sequentially performed.
As described above, the insulating layer is formed on the entire surface including the fuses, and some regions of the fuses are subjected to laser blowing. However, as a pattern size reduces, the blowing size also reduces accordingly. Thus, in order to accurately target a specific area, a laser used should be adjusted to have a smaller wavelength and higher energy density. When the laser blowing is performed using a laser having higher energy density, laser energy radiated is undesirably transferred down to the semiconductor substrate, damaging the substrate.